A U.S. Army CH-47 Chinook helicopter transporting a Humvee prepares to land at a forward operating base. A U.S. Army CH-47 Chinook helicopter transporting a Humvee prepares to land at a forward operating base in southern Afghanistan on March 4, 2010. The Chinooks are the Army's primary cargo rotary aircraft and have been crucial throughout Operation Enduring Freedom. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 106552-L-IXJ40-839.jpg Photo Gallery